An optical delay line can be used to separate the particular colors of a chromatic spectrum. An example of such a device is an array waveguide grating (AWG). If a conventional AWG is designed for extremely high color resolution, the AWG must have great physical size. This size can easily exceed that of a common silicon wafer.
There is thus a need for an optical delay line that provides high color resolution but that is compact. For many applications it is desirable that such a delay line be realizable in planar form. An optical delay line having these attributes can enable a very high resolution AWG system (a hyper-resolution AWG system).